WO1998034505A1 - Composite textile material for protecting the human body against heat - Google Patents

Abstract

The invention concerns a composite textile material for protecting the human body against heat, essentially comprising an external zone ensuring impermeability, an intermediate zone in which an air flux circulates and an internal zone ensuring the mass transfer and the heat transfer towards the intermediate zone. The invention is characterised in that it consists of a three-dimensional fabric (1, 3, 4) with one cloth (1) in hydrophobic fabric constituting the external zone and the other cloth (4) is a cloth woven or knitted with hydrophilic fibres constituting the internal zone, the two cloths (1, 4) being linked by linking threads (5) providing the intermediate zone.

Description

MATER IAU TEXT ILE COMPOSITE PROTECTING ION OF THE HUMAN BODY AGAINST HEAT

The invention relates to a composite textile material for protecting the human body against heat, in particular making it possible to increase the efficiency of the surface ventilation of the human body with a view to ensuring the comfort or even the survival of an individual in hot or very hot environment.

The thermoregulation of the human body in a hot environment is essentially based on lowering the temperature of the skin, by conduction, convection, radiation and evaporation of sweat, and to a lesser extent, by convection and evaporation in the lungs.

When the existing climate or the micro-climate created close to the body (essentially temperature and humidity) limits the exchanges described above until compromising the comfort or even the survival of the individual, two methods are used: ventilation '' dry, relatively cool air (up to 4 to 5 ° C below skin temperature); b / the contact of a body with high specific heat or high latent heat of transformation, this body having been previously cooled.

The first method is particularly advantageous from three points of view: efficiency, flexibility of use and comfort; the second method is generally limited to the case where the environment does not allow a source of dry and relatively fresh air to be available. However, even the current systems based on air ventilation are not entirely satisfactory, on the one hand because the energy balance can prove to be poor in certain cases: there is for example a ratio of 1 to 10 between the useful power and the power supplied in the case of the air conditioning of an individual in a passenger compartment of a car. In addition, unoptimized air consumption when using protective equipment against chemical, biological, nuclear or thermal attack (fire-resistant clothing) harms its autonomy. In fact, the risks of hyperthermia or the appearance of liquid sweat which can cause injury in the event of exposure to high temperatures require the use of relatively heavy or bulky ventilation or air conditioning equipment or limit the duration of l intervention of the individual wearing this equipment.

It would therefore be good to have a system to improve the efficiency of the ventilation of the human body, in particular by maintaining special conditions of temperature and humidity on privileged areas of the human body such as the torso, the arms , the thighs, the skull, the back and in any event, on a surface sufficient to evacuate the power necessary according to the thermal resistance of the skin, using individual equipment to be connected to a ventilation or air conditioning outside, personal or collective, operating in moderate conditions. Such moderate conditions consist in particular in providing the individual equipment with fresh, dry air at low flow rate, with an exhaust of humid and hot air, and a pressure drop resulting from the circulation of air in the equipment. individual which must be minimal (for example less than 800. Pa). If the outside environment allows, the natural ventilation generated by the wearer's movements may be sufficient and not require forced ventilation.

The problem is solved according to the invention by using for the individual equipment a composite textile material, essentially comprising:

- an external zone ensuring a sealing function, - an intermediate zone allowing the circulation of an air flow and

- an internal zone ensuring mass transfer and thermal transfer from the individual to the intermediate zone. For the purposes of this patent application, the qualifier "external" designates an element directly or indirectly facing the environment in which the individual is immersed while the qualifier "internal" designates an element directly facing (in contact from the skin) or indirectly (contact with clothing) to the individual.

To produce such a structure of composite material, a three-dimensional textile is advantageously used either alone or in combination with other textiles.

Three-dimensional textiles are relatively new products and consist of two fabrics joined by connecting threads.

In general, three-dimensional textile connecting threads have properties of size, resilience and density such that they make it possible to obtain a textile material having a relatively constant thickness for a given fabric but which can be fixed by example between 3 and 30 mm, or even more. At present, three-dimensional fabrics find applications in the field of protective clothing because of their anti-shock property or the presence of an air space in their internal volume (fire protection).

The three-dimensional fabric connection threads, which are for example made of polyamide, provide, due to their flexural modulus and their density, good compressive strength in the direction perpendicular to the fabric by allowing air circulation in three-dimensional fabric, even at possible compression points, as well as a low pressure drop. These two characteristics are specific to three-dimensional fabrics and are not found in foams, for example of the polyurethane type, conventionally used as padding material. On the other hand, the connecting wires capture the liquid sweat and promote its evaporation.

The material according to the invention can therefore consist of a simple three-dimensional fabric, formed of two fabrics or fabrics, asymmetrical as to their composition or of a "symmetrical" three-dimensional fabric to which are added the fabrics or fabrics ensuring the necessary sealing and transfer functions.

The sealing function, the main objective of which is to limit the leakage of air flowing in the three-dimensional fabric, is provided by a fabric, possibly coated (for example a polyester fabric coated with polyurethane). This fabric can constitute the external face of the three-dimensional fabric, or can be a complementary fabric to the external face of the three-dimensional fabric. The waterproofing function should not be total if the fabric is used for the manufacture of a garment because the outer layer must be able to allow sufficient exchange between the body and the environment to allow the wearing of equipment when it there is no air circulation in the intermediate zone.

The transfer function is provided by an internal layer, for example a fabric or knitted fabric, of polyester, polyamide or polyacetate type fiber or one of their mixtures, treated hydrophilically, and having good liquid transfer power, good drying power and good permeability to water vapor. This internal layer can constitute the second face of the three-dimensional fabric or an element dissociated from the latter. In the latter case, it is preferable that the second face of the three-dimensional fabric is sufficiently perforated so as not to slow down the heat transfer and the mass transfer between the interior of the three-dimensional fabric and the material constituting the internal layer.

Such a textile material is used, for example in the form of a garment covering certain parts of the body or in the form of a seat or sleeping covering, this covering then being in contact with an individual dressed or not. In both cases, the air flow is circulated via a diffuser located after an air intake fitting, and a manifold located before an exhaust fitting. The diffuser and the collector are created in the thickness of the composite textile material by continuous or non-continuous seams which channel the air flow. In the same way, using continuous or non-continuous seams, it is possible to create preferential paths between the diffuser and the collector to distribute fresh and dry air according to a pre-established circulation. A diffuser, a collector and possibly preferential paths can also be created in a similar manner in a seat or sleeping covering.

The composite textile material and the products produced therefrom according to the present invention provide thermoregulation of comfort or even survival in a hot environment of an individual, and find application in particular in the following cases:

1 / protection of an individual residing in a confined space, of the cockpit, sleeping bag or similar type, 2 / wearing of an outfit preventing the natural transfer of sweat and body heat to the external environment by reducing operational or autonomy characteristics of the individual, such an outfit being able to be a ballistic, chemical, thermal, vapor or fire protection suit. In addition, in addition to the new advantages according to the present invention, the use of a three-dimensional fabric in certain types of clothing or protections continues to provide certain known and interesting effects: in ballistic protection, the material contributes to the reduction of the rear effect and can be integrated into the protection itself as an anti-trauma layer; and in thermal, steam or fire protection, it reduces heat transfer by conduction and convection and can also be integrated into the protection.

The invention will now be described in more detail with reference to the accompanying drawings in which: FIG. 1 is a sectional view of a first embodiment of a composite textile material,

FIG. 2 is a sectional view of a second embodiment of a composite textile material,

FIG. 3 is a sectional view of another mode of organization of the material,

FIG. 4 is a sectional view of yet another embodiment of the textile material, FIG. 5 is a schematic view of a garment produced with the composite textile material,

FIG. 6 is an enlarged detail of FIG. 5, and

• Figure 7 is a sectional view of a type of preferential path created in a material.

FIG. 1 shows a section of a textile material consisting of an outer layer 1, a space 3 and an inner layer 4. The outer layer and the inner layer are connected by connecting wires 5, constituting what we call it a three-dimensional fabric. The outer layer 1 provides a certain seal, and is for example made of a polyester type hydrophobic fabric, the seal if it must be total can be adjusted using a coating layer 2, for example in polyurethane. In the event that the seal must not be complete in order not to block exchanges in degraded mode (stopping the ventilation device), materials whose composition or construction allow good vapor permeability to be used water while providing between the two faces of the outer layer a sufficient pressure drop to limit air leaks. The inner layer 4 is a fabric or knitted fabric of hydrophilic fibers of the polyester, polyamide or polyacetate type (or a mixture of these fibers) having received a hydrophilic treatment. This fabric or knitted fabric must have good liquid transfer power, which means low priming pressure, high absorption kinetics, and a low level of saturation, as well as good drying power. that is to say a high surface coverage and a high drying kinetics, as well as a good permeability to water vapor.

In this embodiment of FIG. 1, the external zone is constituted by the layer 1 and possibly the coating layer 2; the intermediate zone comprises the space 3 crossed by the connecting wires 5, and the internal zone is constituted by the fabric 4. In the case shown in FIG. 2, the external zone and the intermediate zone have the same structure as in the material of Figure 1 while the internal area is limited by a fabric 6 of the same type as the layer 4 of FIG. 1, this fabric 6 being dissociated from the three-dimensional fabric constituted by the external fabric 1, the space 3 and an additional fabric 7, connecting threads connecting the fabrics 1 and 7. It may then be advantageous for the nature of the fabrics 1 and 7 is the same to simplify the manufacture of the three-dimensional fabric. It is however preferable that the structure of the additional fabric is more perforated (openings 8) so as not to slow down the heat and mass transfers.

The textile materials represented in FIGS. 3 and 4 correspond respectively to those of FIGS. 1 and 2, with the difference that the external zone is constituted by a fabric 1a, possibly provided with the coating layer 2 distinct from the fabric constituting the three-dimensional fabric.

FIG. 5 schematically represents a protective garment produced with a textile material according to the invention. By way of example, this garment 10 comprises a cap 11 connected to a jacket 12 with sleeves 13 and pants 14 with legs 15.

A connection for admission of dry and relatively fresh air 16 from an external ventilation device (not shown) introduces this air into the space 3 of the textile material via a diffusion zone 17 situated for example around the neckline of the garment. This diffusion zone is delimited by a continuous seam 18 and a discontinuous seam 19, the latter allowing diffusion (symbolized by arrows) throughout the space 3. At the base of the jacket 12, a collecting zone 20 is constituted in the same way by a continuous seam 18 and a discontinuous seam 19 and collects the air flow having passed through the jacket by directing it (see FIG. 6) towards an exhaust connection 21 connected to the ventilation device.

A fabric 22 can be added to the internal face of the preferential path (see FIG. 7) to reduce leakage. The hood and the legs can be supplied with dry and fresh air either through the jacket or by diffusion and collection zones supplied by independent circuits. For this purpose, the legs can be fitted with inlet connections 16 'and exhaust 21' with or without the creation of preferential paths by combination of continuous or discontinuous seams.

The textile material can also be used for making seat coverings, coverings for bunks, sleeping bags or the like, by providing each of these materials with a diffusion zone and a collecting zone respectively equipped with a inlet fitting and exhaust fitting connected to a ventilation device.

Claims

RESELL 1 CATIONS 1. Composite textile material for protecting the human body against heat, essentially comprising an external zone ensuring a sealing function, an intermediate zone in which a flow of air circulates and an internal zone ensuring mass transfer and thermal transfer towards the intermediate zone, characterized in that it is constituted by a three-dimensional fabric (1, 3,4) of which a fabric (1) is made of hydrophobic fabric and constitutes the external zone and of which the other fabric (4) is a fabric or knitted fabric of hydrophilic fibers and constitutes the internal zone, the two fabrics (1, 4) being connected by connecting threads (5) ensuring the existence of the intermediate zone. 2. Textile composite material for protecting the human body against heat, essentially comprising an external zone ensuring a sealing function, an intermediate zone in which an air flow circulates and an internal zone ensuring mass transfer and thermal transfer towards the intermediate zone, characterized in that it consists of a three-dimensional fabric (1, 3.7) of which one fabric (1) is made of hydrophobic fabric and constitutes the external zone and the other (7) is identical or different and by a fabric or knitted fabric (6) of hydrophilic fibers spaced from the three-dimensional fabric, the two fabrics (1, 7) being connected by connecting threads (5) ensuring the existence of the intermediate zone. 3. composite textile material according to claim 2, characterized in that the surface of the three-dimensional fabric (7) facing the fabric or knitted fabric (6) is perforated. 4. Textile material according to claim 1, characterized in that the fabric (1) comprises any first layer and a hydrophobic fabric (the) contiguous. 5. Textile material according to claim 2, characterized in that the three-dimensional fabric (1, 3.7) is lined on one side with a hydrophobic fabric (1a) and on the other side with a fabric or knitted fabric (6 ) hydrophilic fibers. 6. Textile material according to either of claims 4 and 5, characterized in that the hydrophobic fabric (1, 1a) carries a coating layer (2). 7. element for protecting the human body made from a composite textile material according to any one of claims 1 to 6, characterized in that it is equipped with an inlet means (16) for a flow air from a source external to the protection element (forced ventilation) or generated by the movements of the wearer (natural ventilation), a diffusion zone (17) distributing the air flow in the internal volume of the three-dimensional fabric, a collecting zone (20) collecting the flow air having circulated in the three-dimensional fabric and an exhaust means (21) of the air flow. 8. Protective element according to claim 7, characterized in that preferential paths have been created in the internal volume of the three-dimensional fabric between the diffusion zone and the collecting zone, by continuous (18) or discontinuous (19) seams.